Field of the Invention
This invention relates to a fluid cooling system for a ram bushing and, more specifically to a fluid cooling system utilizing a low pressure pump.
Background Information
The manufacture of certain containers, such as, but not limited to, aluminum cans, on a bodymaker typically includes a circular or cup-like blank that is disposed on a punch attached to a ram and passed through one or more dies. The friction created when the ram passes through the ram bushing causes the ram bushing to heat up. The heat in the ram bushing is reduced by passing a fluid, such as, but not limited to, oil, through the ram bushing.
Presently, such cooling systems utilize the bodymaker high pressure pump or high pressure system. The amount of fluid from the high pressure system that may be used for cooling is limited. That is, the cooling system provides cooling fluid at a rate of about 3 gpm and at an initial pressure of about 1,000 to 1,200 psi, which is reduced to about 50 psi to 150 psi at the ram bushing. The oil in the high pressure system, however, tends to be hot and the cooling properties of the fluid are limited. Further, a high pressure pump tends to be more expensive and prone to more degradation through use than the bodymaker low pressure pump or low pressure system. It would he desirable to utilize the low pressure system, but the low pressure system, typically, does not provide sufficient pressure or flow rate to effect cooling of the ram bushing. Alternatively, if the flow rate, or pressure, in the low pressure system is increased, the low pressure pump may draw too much power causing degradation to the pump or causing a circuit breaker to trip.